That's a nice guide. I've done the oil changes on my 6i and now I've done 2 on my 3s, one at 400 miles, and one at 3000.
I worked at Jiffy Lube in high school and college and this is one of the cars that the pit guy would hate to work on. The plastic shroud is a pain and so is the internal filter.
Like many of you, I have a "phobia" of taking this car anywhere for oil changes. Actually, it's not really a phobia, because the fear of someone screwing up the oil change on the 2.3L isn't unreasonable.
If you can do it, I'd do it yourself.
For what it's worth, I don't use a torque wrench for oil changes. I've done so many, my elbow clicks when the plug and filter cap are tightened enough
Seriously though, if you replace the drain plug washer every time, you shouldn't need a torque wrench because you can feel the new washer crush, and when it stops crushing, it's tight enough. It doesn't take much at all. You can't tell with an old washer, because it's already crushed.
The filter, I just snug it up hand tight. Not too tight. Until the elbow clicks.
There are things I do use torque wrenches for, like tightening lugs after rotating the tires.